| 摘要 |
<p>PURPOSE:To video record easily a visitor on a video tape by utilizing actions of an annunciator such as a chime for visitor and by operating a monitor television and a video tape recorder through a controller for a certain period. CONSTITUTION:When a chime 1 operates, a controller 3 outputs on-signals for a certain period, which causes a monitor television camera 4 to operate. With the aid of the output of the controller 3, the contents photographed by the camera 4 are video recorded by a video tape recorder 5. When the chime 1 is in the on state, transistors TR7 and TR8 are turned off through lines (a) and (b), and a collector potential of the TR8 becomes ''H''. An output signal from a monostable multivibrator 9 can operates the camera 4 and the recorder 5 accordingly.</p> |
